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(19)

(12)

(43) Date of publication:

30.08.2000 Bulletin 200Q/35

(21 ) Application number: 00200586.6

(22) Date ofjiling: 21 .02.2000

Europaisches Patentamt
European Patent Office
Office europeen des brevets (1 1 ) EP 1 031 580 A1

EUROPEAN PATENT APPLICATION

(51) Int. CI. 7 : C08F 4/60, C08F 10/00

(84) Designated Contracting States:

* Chen, Hong

AT BE CH CY DE DK ES R FR GB GR IE IT LI LU

Alpharetta, Georgia 30005 (US)

MCNLPT SE

• Lopez, Margarito

Designated Extension States:

Pasadena, Texas 77502 (US)

AL LT LV MK RO SI

(74) Representative:

(30) Priority: 22.02.1999 US 255102

Leyder, Francis et al

c/o Fina Research S.A.

(71) Applicant: FINA TECHNOLOGY, INC.

Dept. Brevets

Piano, Texas 75024 (US)

Zone Industrielle C

7181 Seneffe (Feluy) (BE)

(72) Inventors:

• Shamshoun, Edwar S.

Gibsonia, Pennsylvania 15044 (US)

(54) Ziegler-Natta catalyst with metallocene for olefin polymerization

(57) Provided is catalyst system, for polymerization
of monomer having at least one Ziegler-Natta polymer-
izable bond, comprising:

a) supported conventional Ziegler-Natta type transi-
tion metal catalyst component modified with metal-
locene-type catalyst component during its
synthesis or production; and

b) effective co-catalyst.

m
o

CL
LU

Primed by Xerox {UK) Business Services
2.16.7 (HRS)/3.6

EP 1 031 580 A1

Description

Field ol the Invention

5 [0001] This invention relates to catalyst system for polymerization of monomer having at least one Ziegler-Natta
polymerizable bond. It is notably effective with ethylene and other a-olef ins. Particular catalyst systems of this invention
will comprise supported Ziegler-Natta catalyst which has been modified with metallocene-type or single-site catalyst,
preferably during synthesis.

10 Background of the Invention

[0002] Polyolef in manufacturing processes typically involve the polymerization of olefin monomer with an organo-
metallic catalyst of the Ziegler-Natta type. Catalyst systems for the polymerization of olefins are well known in the art.
Typically, these systems include a Ziegler-Natta type polymerization catalyst component and a co-catalyst, usually an
15 organoaluminum compound.

[0003] U.S. 4,530.914 discloses use of a catalyst system comprising two or more metallocenes in the polymeriza-
tion of a-olefins, primarily ethylene, to obtain a broad molecular weight distribution. The metallocenes each have differ-
ent propagation and termination rate constants. Such metallocenes are mixed with an alumoxane to form the active
catalyst system.

20 [0004] U.S. Patent 4,701 ,432 describes a support treated with at least one metallocene and at least one non-met-
allocene transition metal compound. To form a catalyst system a cocatalyst comprising an alumoxane and an organo-
metallic compound of Group IA, IIA, MB, and IHA is added to the supported metal locene/non-metallocene. The support
is a porous solid such as talc or inorganic oxides or resinous materials, preferably an inorganic oxide, such as silica,
alumina, silica-alumina, magnesia, titania, or zirconia in finely divided form. By depositing the soluble metallocene on

25 the support material it is converted to a heterogeneous supported catalyst. The transition metal compound, such as
TiCI 4 . is contacted with the support material prior to, after, simultaneously with, or separately from contacting the met-
allocene with the support.

[0005] It is known that CD2T1CI2 in the presence of alkylaluminum compounds polymerizes ethylene but not propyl-
ene whereas in the presence of methylalumoxane (MAO). CP2T1CI2 polymerizes propylene also to produce atactic poly-
30 propylene. Combination of dimethyl titanocene and its Cp-substituted analogues and TiCI 3 for propylene
polymerizations has been reported in U.S. 2,992,212 and by G.A. Lock in Thermoplastic Elastomers Based on Block
Copolymers of Ethylene and Propylene", Advances in Polvolef ins (Seymour, Raymond B.. ed.) at pages 59 - 74. MAO
was not used in this polymerization.

[0006] Typically catalysts for traditional polymerization of olefin monomer include a Ziegler-Natta-type polymeriza-
35 tion catalyst component, a co-catalyst which is generally an organoaluminum compound, and an external electron
donor or selectivity control agent, often an organosilicon compound. Such catalysts are described in U.S Patents
4,107.413; 4.294,721 ; 4.439,540; 4,1 15.319; 4.220,554; 4.460.701 ; and 4.562,173.

[0007] U.S. Patent 4.530,91 4 discloses use of a catalyst system comprising two or more metallocenes in the polym-
erization of a-olefins, primarily ethylene, to obtain broad molecular weight distribution. Such metallocenes each have

40 different propagation and termination rate constants and are mixed with an alumoxane to form the catalyst system.
[0008] U.S. Patent 4.808.561 discloses reacting a metallocene with an alumoxane and forming the reaction product
in the presence of a support; a porous material such as talc, inorganic oxides such as those of Groups IIA. I IIA, IVA, or
1VB metal oxides such as silica, alumina, silica-alumina, magnesia, titania, zirconia and mixtures thereof, and resinous
materials such as polyolefins. particularly finely divided polyethylene. The disclosures of these patents are hereby

45 incorporated by reference.

[0009] A Ziegler-Natta type polymerization catalyst generally is basically a complex derived from a halide of a tran-
sition metal, for example, titanium, chromium or vanadium with a metal alkyl, typically an organoaluminum compound,
as a co-catalyst. The catalyst is usually comprised of a titanium halide supported on a magnesium compound com-
plexed with an alkylaluminum co-catalyst.

so [001 0] It is known that two or more homogeneous catalysts, such as those based on metallocene compounds, may
be combined to effect properties, such as molecular weight distribution. U.S. Patent No. 4.530.914 discloses use of a
catalyst system comprising two or more metallocenes in the polymerization of a-olefins, primarily ethylene, to obtain a
broad molecular weight distribution. The metallocenes each have different propagation and termination rate constants.
The metallocenes are mixed with an alumoxane to form the catalyst system.

55 It is also known that metallocenes may be affixed to a support to simulate a heterogeneous catalyst. U.S. Patent No.
4,808,561 discloses reacting a metallocene with an alumoxane and forming a reaction product in the presence of a sup-
port. The support is a porous material like talc, inorganic oxides such as Group IIA, IMA IVA or IVB metal oxides such
as silica, alumina, silica-alumina, magnesia, titania, zirconia and mixtures thereof, and resinous material such as poly-

EP 1 031 580 A1

olefins, e.g., finely divided polyethylene. The metallocenes and alumoxanes are deposited on the dehydrated support
material.

1001 1] In U.S. Patent No. 4,701 .432 it is taught that a support is treated with at least one metallocene and at least
one non-metallocene transition metal compound. To form a catalyst system a cocatalyst comprising an alumoxane and

5 an organometallic compound of Group IA, IIA, MB and MIA is added to the supported metallocene/non-metallocene. The
support is a porous solid such as talc or inorganic oxides or resinous materials, preferably an inorganic oxide, such as
silica, alumina, silica-alumina, magnesia, titania or zirconia, in finely divided form. By depositing the soluble metal-
locene on the support material it is converted to a heterogeneous supported catalyst. The transition metal compound,
such as TiCI 4 , is contacted with the support material prior to. after, simultaneously with or separately from contacting

w the metallocene with the support.

[001 2] It is known that Cp 2 TiCI 2 in the presence of alkylaluminum compounds polymerizes ethylene but not propyl-
ene whereas in the presence of methylalumoxane (MAO) Cp 2 TiCI 2 polymerizes propylene also to produce atactic poly-
propylene. Combination of dimethyl titanocene and its Cp-substituted analogues and TiCI 3 for propylene
polymerizations has been reported in U.S. Patent No. 2,992,212 and in "Thermoplastic Elastomers Based on Block

is Copolymers of Ethylene and Propylene", G. A. Lock, Advances in Polvolefins. p. 59-74, Raymond B. Seymour, Ed. MAO
was not used in this polymerization.

[0013] Use exists for improvement of conventional or traditional Ziegler-Natta catalyst activity without the expense
and safety concerns of use of pure metallocene-type catalyst systems. Our invention fills this need and alters polymer
properties in polymerization processes by use of a supported Ziegler-Natta catalyst which has been modified by met-
20 all ocene -type catalyst compound.

Summary of the Invention

[0014] Our invention provides means to change polymer properties in polymerization processes using a supported
25 Ziegler-Natta catalyst which has been modified with a metallocene compound.

[0015] We further provide means to produce polymerized monomer, particularly polyolefin, having low molecular
weight and narrow molecular weight distribution.

[001 6] Additionally we provide improved catalyst activity by modif iying conventional Ziegler-Natta catalyst, prefera-
bly during synthesis.

30 [0017] Such provisions are accomplished by catalyst system comprising a supported conventional Ziegler-Natta
catalyst modified with a metallocene compound used in polymerization of monomers, notably olefins, especially ethyl-
ene.

Brief Description of the Drawings

[0018]

Figure 1 provides a graphic presentation of Cp 2 TiCI 2 : Mg(OEt) 2 molar ratio v. polymer yield.
Figures 2 and 3 provide infrared (IR) spectra for Cp^iCI^ the catalyst precursor, and the catalyst made from 3:1
40 reaction of Mg(OEt) 2 and Cp 2 TiCI 2 , respectively.

Detailed Description of the Invention

[0019] To assist in clearly defining our invention, it is useful to understand that when the term "metallocene-type
45 catalyst" is used, we intend those catalyst components functioning in a manner similar to metallocenes. We intend also
that which is not conventional or traditional Ziegler-Natta catalyst but which will polymerize Z-N-accessible (polymeriz-
able) bond. Examples of such species include the well known bis-cyclopentadienyl ring ligands-bearing transition metal
molecules, mono-cyclopentadienyl and heteroatom ligands-bearing molecules; and other known similarly functioning
non-Cp, multi-"heteroatom" molecules such as those described in US 5.227,440; US 5,264,405; US 5,318,935; and US
so 4,774,301 among others. Useful and effective cocatalysts will include organoaluminums such as aluminum alkyls and
alumoxanes as well as other activators such as the irreversibly reacting large, labile anions of Hlatky and Turner partic-
ularly those described in U.S. 5.470,927; 5,384,299; and 5,198,401 ; also those of U.S. 5.621,126 and the cationic or
cataqlyst component species described here as well.

[0020] Our invention provides catalyst system, for polymerization of monomer having at least one Ziegler-Natta
55 polymerizable bond, comprising:

a) supported conventional Ziegler-Natta type transition metal catalyst component modified with metallocene-type
catalyst component during its synthesis or production; and

EP 1 031 580 A1

b) effective co-catalyst.

[0021] In another embodiment, our invention provides process for polymerization of monomer having at least one
Ziegler-polymerizable bond comprising steps of:

a) selecting catalyst system comprising:

i) supported conventional Ziegler-Natta type transition metal catalyst component modified with metallocene-
type catalyst component during its synthesis or production; and
10 ii) effective co-catalyst;

b) selecting monomer to be polymerized;

c) contacting monomer with catalyst system under suitable conditions of time and temperature to initiate polymer-
ization;

is d) optionally stopping polymerization after brief contact to effect pre-polymerization;

e) continuing contact of monomer with catalyst system to accomplish desired polymerization; and

f) separating desired polymer.

[0022] Yet another embodiment of our invention provides synthesis of catalyst system, for polymerization of mono-
20 mer having at least one Ziegler-Natta polymerizable bond, comprising steps of:

a) selecting component comprising magnesium dialkoxide of the general formula Mg(OR 2 ) 2 where R 2 is a hydro-
carbyl or substituted hydrocarbyl of 1 to 20 carbon atoms;

b) combining with metallocene-type catalyst component-supplying agent;
25 c) adding halogenating, preferably chlorinating, agent;

d) adding titanating agent, which may optionally be the same as halogenating agent; and

e) providing effective cocatalyst.

[0023] A further embodiment of our invention provides polymer produced by polymerization of monomer having at
30 least one Ziegler-polymerizable bond in the presence of catalyst component, comprising; supported conventional Zie-
gler-Natta type transition metal catalyst component modified with metallocene-type catalyst component during its syn-
thesis or production.

[0024] For each of the previously described embodiments of our invention, a preferred embodiment uses metal-
locene-type catalyst component comprises at least one ligand comprising cyclopentadienyl ring structure. Effective
35 cocatalyst includes those which comprise aluminum compound.

[0025] A preferred embodiment of the transition metal compound are those of the general formula MR 1 X where the
metal, M, is group 4 metal, R 1 is halogen or hydrocarbyloxy, and x is the valence state of metal. Further useful catalyst
systems will use aluminum compound comprising organoaluminum.

[0026] Notably preferred catalyst systems will be those wherein Group 4 metal is titanium, organoaluminum which
40 are aluminum alkyl of the formula AIR* 3 where R' is an alkyl having 1-8 carbon atoms, each R' is the same or different,
or their combinations.

[0027] Polymer product separated upon use of our invention will have generally narrow molecular weight distribu-
tion. Ziegler-Natta catalyst usefully may be pre-poiymerized to improve the performance of the catalyst. Generally, pre-
polymerization is effected by contacting a small amount of monomer with the catalyst after the catalyst has been
45 contacted with the co-catalyst. Pre-polymerization is described in U.S. Patent Nos. 4,767,735, 4,927.797 and
5,122,583, hereby incorporated by reference.

[0028] Any of the conventional supported Ziegler-Natta transition metal compound catalyst components can be
used in the present invention. The transition metal compound is preferably of the general formula MR 1 X where M is the
metal, R 1 is a halogen or a hydrocarbyloxy and x is the valence of the metal. Preferably, M is a Group IVB metal, more

so preferably a Group IVB, and most preferably titanium. Preferably, R 1 is chlorine, bromine, an alkoxy or a phenoxy, more
preferably chlorine or ethoxy and most preferably, chlorine. Illustrative examples of the transition metal compounds are
TiCI 4 , TiBr 4 , Ti (OCaHshCI, Ti (OC^HshCI. Ti (OCaHyfeClg. Ti (OC 6 H 13 ) 2 Cl2. Ti (OC2H 5 ) 2 Br 2 and Ti (OC 12 H25)CI 3 .
Mixtures of the transition metal compounds may be used. No restriction on the number of transition metal compounds
is made as long as at least one transition metal compound is present.

55 [0029] The support should be an inert solid which is chemically unreactive with any of the components of the con-
ventional Ziegler-Natta catalyst. The support is preferably a magnesium compound. Examples of the magnesium com-
pounds which are to be used to provide a support source for the catalyst component are magnesium halides.
dialkoxymagnesiums, aikoxymagnesium halides, dialkylmagnesiums, magnesium oxide, magnesium hydroxide, and

EP 1 031 580 A1

carboxylates of magnesium. The preferred magnesium compounds are magnesium halides, notably magnesium chlo-
ride

[0030] The organoaluminum co-catalyst is preferably an aluminum alkyl of the formula AIR* 3 where R* is an alkyl
having one through about eight carbon atoms, each of the alkyl groups may be the same or different, tramples of alu-
minum alkyls are trimethyl aluminum (TMA), triethyl aluminum (TEAI) and triisobutyl aluminum (TiBAI). The preferred

aluminum a|M JjJ^^ compound ^ be a cy dopentadienide. i.e.. a metal derivative of a cyclopentadiene. The
metallocene should contain at least one cyclopentadiene ring and be of the general formula:

R"n(CpRs-n)a(CpR'5-n)bM'RV< a+ b)

where Cp is a cyclopentadienyl ring. R and R' are substituents on the cyclopentadienyl rings and can be a hydride or a
hydrocarbyl from 1 -9 carbon atoms, each R and R' being the same or different, each (CpRg-n) and (CpR s-n) being the
same or different, a and b are 0 or 1 . indicating whether the particular Cp ring is present, but at least one of a or b must
be V R" is a structural bridge between (CpR^a and (CpR's-Jb to impart stereorigidrty, n be.ng 1 or 0 to indicate
whether the bridge is present or not and when n=1 . a and b both must equal 1 ; M' is Group IVB metal. R « a hydride
a halogen or a hydrocarbyl from 1-20 carbon atoms, v is the valence of NT. Preferably, a is 1 and b is 1 , (CpRs-n) and
(CpR's J are the same and are cyclopentadienyl rings such that they are unsubstituted cyclopentadienyl and n is 0. Le.,
unbridged. Preferably. NT is titanium, which have valences of 4. Preferably. R is a halogen or alkyl, most preferably chlo-
rine. The standard synthesis procedure for prior art conventional Ziegler-Natta catalysts follows:

a) selecting a solid component comprising magnesium dialkoxide of the general formula MgpR 2 )-, where R 2 is a
hydrocarbyl or substituted hydrocarbyl of 1 to 20 carbon atoms;

b) adding a chlorinating agent:
ss c) adding a titanating agent; and

d) adding an organoaluminum co-catalyst.

The chlorinating agent and the titanating agent may be the same compound, e.g. a titanium chloride, specifically tita-

[O^^^'synthSte procedure for Ziegler-Natta type catalysts for the polymerization of olefins is disclosed in U.a
Patents the disclosures of which are hereby incorporated. The present invention modifies the synthesis procedure, and
thus modifies the catalyst, by adding a metallocene compound during the synthesis process. Our synthesis for the cat-
alysts of this invention follows:

a) selecting component comprising magnesium dialkoxide of the general formula Mg (OR 2 ) 2 where R 2 is a hydro-
carbyl or substituted hydrocarbyl of 1 to 20 carbon atoms, a magnesium diethoxJde is usefully applied here;

b) combining with metallocene-type catalyst component-supplying agent;

d) Sd'hra "reactive Group 4"agent. titanium tetrachloride functions well for both steps c) and d) here and heating
40 at this point promotes thorough reaction of the components, at which point washing the product with solvent hep-
tane is notably effective, to purify the product, following with heat treatment again will assist in solvent removal, the
product is usefully dried at this point, drying under vacuum will assist in speeding drying; and

e) providing effective cocatalyst; organoaluminums. notably triethylaluminum, will function beneficially here.

45 As shown, metallocene-type catalyst compound was added prior to the addition of titanium tetrachloride The amount
of metallocene added is such that a molar ratio of magnesium dialkoxide/titanocene to (Mg/Ti) is at least 1 :1 . preferably
about 1:1 to about 1:4, more preferably about 1:3. . „

[00331 The invention having been generally described, the following examples are given as particular embodiments
of the invention and to demonstrate the practice and advantages thereof, ft is understood that the examples are given

so by way of illustration and are not intended to limit the specification or the claims to follow in any manner.

Preparation of the Catalyst

Preparation of catalyst precursor from reaction of CpjTiCIa and Mg(OEt)2

[00341 Unless otherwise stated, all manipulations were conducted under inert atmosphere. Mg(OEt) 2 was dried in
vacuo at 120-C for 20 hours. Heptane and toluene were purified by passing through a 3A molecular sieve column, an
F200 alumina column and then a column f illed with copper catalyst at a rate of 12 ml/min. Octane was dried over

EP 1 031 580 A1

sodium metal and distilled prior to use.

[0035] For a typical preparation, 20 g Cp2TiCI 2 and a certain amount of Mg(OEt) 2 (depending on the desired molar
ratio) were weighed into a 500 ml, 3-neck round-bottom flask equipped with a 60 ml dropping funnel and a condenser
with a gas inlet in the dry box. The flask was placed in a mineral oil bath and the solid was suspended in 200 ml toluene.

5 The slurry was heated to reflux (oil bath temperature at 120°C) and stirred overnight (16-21 hours). The color of the
reaction mixture turned from red to brown within one hour and, eventfully, to green overnight. The reaction mixture was
cooled to 60°C and allowed to settle. The supernatant was decanted via a cannula and the solid was washed three
times with toluene. The final solid was dried in vacuo at 60°C for two hours. In the case of 4:1 Mg(OEt) 2 :Cp 2 TiCI 2 reac-
tion, the settling of the reaction mixture was slow. Therefore, the supernatant was decanted as much as possible and

w the rest of the slurry was dried in vacuo at 60°C for two hours. The color of the resultant solid ranged from yellow-green
to blue-green depending on the Mg(OEt) 2 and Cp2TiCI 2 ratio. The lower the ratio, the darker the color of the catalyst
precursor.

Reaction with the Group 4 agent of the Catalyst Precursor

[0036] Five grams (g) of the solid made from the reaction above was suspended in 1 00 ml heptane in a 250 ml flask
and heated to reflux. 12 ml TiCI 4 was added drop-wise to the stirred suspension over 45 minutes. The reaction mixture
was stirred at 98°C for 5.5 hours, during which time the color of the solid turned brown. The reaction mixture was then
cooled to 70 °C and allowed to settle. The supernatant was decanted via a cannula and the solid was washed four times
20 with 50 ml heptane. The solid residue was then re-slurried in 50 ml octane and heated at 1 20 °C for 1 8 hours. After the
heat treatment, the slurry was cooled to 70 °C and allowed to settle. The supernatant was decanted and the solid was
dried in vacuo at 70 °C for two hours. The color of the final catalyst was brown.

(1 ) Syntheses of the Catalyst Precursor and the Catalysts

[0037] A schematic synthesis for each the catalyst precursor, with the metallocene-type modifier, and the actual
polymerization catalyst is provided below. The precursor is demonstrates useful results and is preferably produced
when the ratio of n/m equals about one through about four.

30 toluene wash dried in

nMg(OEt)2 + mCp2TiCl2 — > > >catalyst precursor

reflux 3 times vacuo, 70 °C

Catalyst precursor TiC14 /heptane wash octane dry in

> > > > catalyst

35 98 *C,5.5h w/heptane 120 °C, 18h vacuo

Polymerizations

[0038] A four liter reactor fitted with four mixing baffles with two opposed pitch mixing propellers was used for the
polymerization of ethylene. Ethylene and hydrogen were introduced to the reactor vessel via mass flow controllers while
45 a dome loaded back-pressure regulator keeps the internal reaction pressure constant. The temperature is maintained
in the reactor jacket by steam and cold water using a valve lined to a controller.

[0039] Hexane is used as diluent and triethyl aluminum (TEAL) is used as cocatalyst for all polymerizations.

Polymerization conditions

[0040]

Temperature

80 °C

Reaction Time

60 minutes

EP 1 031 580 A1

(continued)

Catalyst

10 mg

Cocatalyst

TEAL @ 0.25 mmole/1

Flow rates

H 2 /C 2 + at about 2-8 SLPM

Butene

0, 200 or 300 cc/min

[0041] Without limiting the scope of the invention or claims, it is believed that metallocene is 'imported into the
catalyst chemically by the reaction of Mg(OEt) 2 and CftTlC1 2 . During this step, at least part of the Mg(OEt) 2 is chlorm-
ated by Cp 2 TiCI 2 to form Mg(OEt) x CI 2 . x .

Mg(OEt) 2 + Cp^TiCIs Mg(OEt)xCI 2 . x + Cp 2 TiCl x (OEt) 2 . x (x=0,1)

[0042] The chemical exchange between Mg(OEt) 2 and Cp 2 TiCI 2 leading to metallocene incorporation is evidenced
by the color change of the reaction mixture as well as the composition change as shown in Table 1.

Table 1

OEt% and Ti% in Catalyst Precursor and Corresponding Catalyst

%OET

%Ti

Mg(OEt) 2 /Cp 2 TiCI 2

Catalyst Precursor

Catalyst

Catalyst Precursor

Catalyst

1:1

15.9

3.9

9.7

11.7

2:1

12.9

5.8

6.3

9.3

3:1

16.1

3.1

5.2

11.1

4:1

31.1

2.3

5.9

11.1

[00431 The OEt% in the catalyst precursor ranges from 13% to 31%, down from 80% for the starting material
ZoEtK indicating extensive reaction between Mg(OEt) 2 and C^TiC^ when the Mg(OEt) 2 : C£ 2 T.CI 2 ratio .ncreas^.
OEt% increases. understandably so because of the extent of the reaction. Also when the Mg£Et) 2 ™* ea *£ » e
color of the catalyst precursor changes from blue-green to yellow-green. The higher the MgfOEtk . CpzT.CIz ratio, the
fess metaLene'is incorporated into the catalyst precursor, and therefore the lighter the color ™e catalyst precursor
from 1 1 reaction of Mg(OEt) 2 and CpzTiCfe contains very likely some of the unreacted Cp2T.CI2wh.chis only partially
soluble in toluene and will remain in the catalyst precursor resulting in darker color than the others The existence of
Cp 2 T.CI, in the catalyst precursor from 1 :1 reaction is also evidenced by the hydrogen response of that catalyst
10044] The IR spectra of the catalyst precursor and its corresponding catalyst after titanat.on also show the evi-
dence of metallocene incorporation into the catalyst matrix. Shown in Figures 1-3 are specfra of Cp^Cfe «n , cataly*
precursor and the catalyst made from 3:1 reaction of Mg(OEt) 2 and C^TiCIa- Most charactenstic are the bands near
1800 1900 and 31 10 cm- 1 which are characteristic of the Cp groups from the metallocene.

[0045] After reaction with the Group 4 agent, preferably a titanating agent to provide titanation more ethoxKtes are
removed and more titanium were incorporated into catalyst. Therefore, there is a decrease of OEt% and .ncrease of

Ti% from the catalyst precursor to the catalyst. .

[0046] Table 2 summarizes the polymerization results with the catalysts prepared fro ^anous^mola ir rates of
Mg(OEt), and CpaTiClj. As shown in Table 2, the activity for the catalysts varies sgnrf .cantly wrth Mg(OEt); , \o CP2TO2
ratio. The catalys? prepared from 3:1 ratio showed the best activity toward ethylene polymerization (2WO0 ^OcatA.).
while the productivity of the catalyst prepared from 2:1 ratio (20.900 g/cat/h) from also demonstrated good acfjv.ty. The

catalyst precursor itself is not active toward ethylene polymerization. , .

[0047] The hydrogen response for the catalysts also varies with Mg(OEt) 2 to CP2T.CI2 ratio. The hydrogen
esponse of the catalyst increases with the decrease of the Mg(OEt) 2 : C^T.CI, ratio withthe exception £*e1 : 1
ratiocatalyst. The poor hydrogen response of the catalyst prepared from 1:1 rat.o .s probably due to the res.dual
Cp 2 TiCI 2 in the catalyst. Because the relative amount of CpaT.CIa for the reaction to make the catalyst precursor .s the
highest among the four catalysts, and because CfcT.CI, is only partially soluble in toluene ^^""[^
Cp,T.CI, remained in the catalyst precursor during the washes and eventually m the f.nal catalyst. We have learned
from other study that the addition of metallocene can dramatically decrease the hydrogen response of typ.cal catalyst.

EP 1 031 580 A1

possibly related to hydrogenation activity of metallocene.

[0048] The molecular weight distribution for polymers made with the catalysts becomes narrower when the ratio
between Mg(OEt) 2 and CpaTiClg decreases. Polymers made from the catalyst prepared form 2:1 ratio and the catalyst
prepared from 3:1 ratio seem to have very similar properties in terms of melt flow index and molecular weight distribu-
s tion.

Table 2

Mg/Cp ratio

Yield (g)

B.D. (g/cc)

M15

HLMI

DENS

0.29

0.178

2.22

0.9505

4.8

3.9

209

0.26

4.40

45.89

0.9594

5.5

4.9

262

0.29

4.03

44.06

0.9595

5.8

5.4

157

0.32

1.16

8.68

0.9582

7.3

5.3

[0049] A new approach to prepare Ziegler-Natta type catalysts involves the treatment of magnesium ethoxide with
titanocene dichloride prior to TiCI 4 treatment. Different reactant ratios resulted in different catalyst activity and polymer
20 properties. Preliminary screening of these catalysts showed excellent catalyst activity and hydrogen response for some
catalysts. Generally, hydrogen response of these new catalysts is good while molecular weight distribution seems to be
narrow.

[0050] Clearly, numerous modifications and variations of the present invention are possible in light of the above
teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced
25 otherwise than as specifically described herein.

Claims

1 . Catalyst system, for polymerization of monomer having at least one Ziegler-Natta polymerizable bond, comprising:

a) supported conventional Ziegler-Natta type transition metal catalyst component modified with metallocene-
type catalyst component during synthesis or production; and

b) effective co-catalyst.

35 2. Catalyst of claim 1 wherein metallocene-type catalyst component comprises at least one ligand comprising
cyclopentadienyl ring structure.

3. Catalyst system of claim 2 wherein effective cocatalyst comprises aluminum compound.

40 4. Catalyst system of claim 3 wherein transition metal compound is of the general formula MR 1 X where the metal. M,
is group 4 metal, R 1 is halogen or hydrocarbyloxy, and x is the valence state of metal.

5. Catalyst system of claim 4 wherein aluminum compound is organoaluminum.

45 6. Catalyst system of claim 5 wherein Group 4 metal is titanium.

7. Catalyst system of claim 6 wherein organoaluminum is aluminum alkyi of the formula AIR' 3 where R* is an alkyl hav-
ing 1-8 carbon atoms, each R* is the same or different.

so 8. Process for polymerization of monomer having at least one Ziegler-pcJymerizable bond comprising steps of:

a) selecting the catalyst system of any one of claims 1 to 7;

b) selecting monomer to be polymerized;

c) contacting monomer with catalyst system under suitable conditions of time and temperature to initiate
55 polymerization;

d) optionally stopping polymerization after brief contact to effect pre-polymerization;

e) continuing contact of monomer with catalyst system to accomplish desired polymerization; and

f) separating desired polymer.

EP 1 031 580 A1

9. Synthesis of the catalyst system of any one of claims 1 to 7. for polymerization of monomer having at least one Zie-
gler-Natta polymerizable bond, comprising steps of:

a) selecting solid component comprising magnesium dialkoxide of the general formula Mg(OR 2 >2 where R 2 is
5 a hydrocarbyl or substituted hydrocarbyl of 1 to 20 carbon atoms;

b) combining with metallocene-type catalyst component-supplying agent;

c) adding halogenating agent;

d) adding Group 4 agent, which may optionally be the same as the halogenating agent; and

e) providing effective cocatalyst

10. Polymer produced by polymerization of monomer having at least one Ziegler-polymerizable bond in the presence
of the catalyst system of any one of claims 1 to 7.

EP 1 031 580 A1

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EP 1 031 580 A1

European Patent
Office

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EP 00 20 0586

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Full text of "USPTO Patents Application 10686951"

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